SHA -1
Generate a SHA-1 hash from any text in your browser. Produces a 160-bit digest as 40 hex characters using the browser native crypto.subtle API. Note: SHA-1 is broken for security uses.
Text in, SHA-1 out
Every input maps to a fixed 160-bit digest (40 hex characters). Changing one byte randomises the entire output.
Hello, world!
943a702d06f34599aee1f8da8ef9f7296031d699
What you will use SHA-1 for
SHA-1 fingerprints data so you can detect changes, verify integrity, and build authenticated protocols.
Security audits
Verify that a file you downloaded matches the official checksum.
API authentication
Many APIs sign requests with SHA-1 or HMAC-SHA-1.
File integrity
Detect corruption or tampering across storage and transport.
Tokens & IDs
Build deterministic IDs from input data using SHA-1.
How to generate a SHA-1 hash
Paste your text
Drop any text — UTF-8 is handled automatically.
Set options
Pick lowercase or uppercase.
Click Generate
Or leave auto-hash on for live updates.
Copy or download
Grab the 40-char hex digest.
Frequently asked questions
SHA-1 processes input through the Merkle-Damgård construction, producing a fixed 160-bit digest. It is deterministic and one-way.
SHA-1 collisions were demonstrated (SHAttered, 2017). It is unsafe for signatures and certificates but still used in legacy systems.
No — hashes are one-way. Short or common inputs may be found in rainbow tables, but there is no general decryption.
Usually whitespace, trailing newlines, or line endings (LF vs CRLF). Also confirm both tools UTF-8 encode the input.
Yes. No signup, no limits, no ads. Everything runs entirely in your browser.
About SHA-1 hashing
SHA-1 is a cryptographic hash function in the SHA-2 family standardised by NIST in FIPS 180-4. It compresses arbitrary input into a fixed 160-bit digest.
Properties
- Deterministic — same input always produces the same digest.
- Fixed-size output — 160 bits / 40 hex characters.
- Avalanche — changing one input bit randomises about half the output bits.
- Hardware-accelerated in modern browsers via the Web Crypto API.
When to use which
- SHA-256 — the default for most modern protocols (TLS, JWT, Bitcoin).
- SHA-384 / SHA-512 — when you want a longer digest or run on 64-bit-heavy hardware.
- HMAC-SHA-* — for authenticated messages with a shared secret key.